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<h1>npq_poly</h1><p><span class="helptopic">Normalized central polygon moments</span></p><strong>m</strong> = <span style="color:red>npq_poly</span>(<strong>v</strong>, <strong>p</strong>, <strong>q</strong>) is the PQ'th normalized central moment of the
polygon with vertices described by the columns of <strong>v</strong>.

<h2>Notes</h2>
<ul>
  <li>The points must be sorted such that they follow the perimeter in
sequence (counter-clockwise).</li>
  <li>If the points are clockwise the moments will all be negated, so centroids
will be still be correct.</li>
  <li>If the first and last point in the list are the same, they are considered
as a single vertex.</li>
  <li>The normalized central moments are invariant to translation and scale.</li>
</ul>
<h2>See also</h2>
<p>
<a href="matlab:doc mpq_poly">mpq_poly</a>, <a href="matlab:doc mpq">mpq</a>, <a href="matlab:doc npq">npq</a>, <a href="matlab:doc upq">upq</a>, <a href="matlab:doc Polygon">Polygon</a></p>
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